package org.apache.maven.repository.internal;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

import java.util.Properties;

import org.eclipse.aether.DefaultRepositorySystemSession;
import org.eclipse.aether.artifact.DefaultArtifactType;
import org.eclipse.aether.collection.DependencyGraphTransformer;
import org.eclipse.aether.collection.DependencyManager;
import org.eclipse.aether.collection.DependencySelector;
import org.eclipse.aether.collection.DependencyTraverser;
import org.eclipse.aether.impl.ArtifactDescriptorReader;
import org.eclipse.aether.impl.DefaultServiceLocator;
import org.eclipse.aether.impl.MetadataGeneratorFactory;
import org.eclipse.aether.impl.VersionRangeResolver;
import org.eclipse.aether.impl.VersionResolver;
import org.eclipse.aether.util.artifact.DefaultArtifactTypeRegistry;
import org.eclipse.aether.util.graph.manager.ClassicDependencyManager;
import org.eclipse.aether.util.graph.selector.AndDependencySelector;
import org.eclipse.aether.util.graph.selector.ExclusionDependencySelector;
import org.eclipse.aether.util.graph.selector.OptionalDependencySelector;
import org.eclipse.aether.util.graph.selector.ScopeDependencySelector;
import org.eclipse.aether.util.graph.transformer.ChainedDependencyGraphTransformer;
import org.eclipse.aether.util.graph.transformer.ConflictResolver;
import org.eclipse.aether.util.graph.transformer.JavaDependencyContextRefiner;
import org.eclipse.aether.util.graph.transformer.JavaScopeDeriver;
import org.eclipse.aether.util.graph.transformer.JavaScopeSelector;
import org.eclipse.aether.util.graph.transformer.NearestVersionSelector;
import org.eclipse.aether.util.graph.transformer.SimpleOptionalitySelector;
import org.eclipse.aether.util.graph.traverser.FatArtifactTraverser;
import org.eclipse.aether.util.repository.SimpleArtifactDescriptorPolicy;

/**
 * A utility class to assist in setting up a Maven-like repository system. <em>Note:</em> This
 * component is meant to assist those clients that employ the repository system outside of an IoC
 * container, Maven plugins should instead always use regular dependency injection to acquire the
 * repository system.
 * 
 * @author Benjamin Bentmann
 */
public final class MavenRepositorySystemUtils {

  private MavenRepositorySystemUtils() {
    // hide constructor
  }

  /**
   * Creates a new service locator that already knows about all service implementations included in
   * this library. To acquire a complete repository system, clients need to add some repository
   * connectors for remote transfers.
   * 
   * @return The new service locator, never {@code null}.
   */
  public static DefaultServiceLocator newServiceLocator() {
    DefaultServiceLocator locator = new DefaultServiceLocator();
    locator.addService(ArtifactDescriptorReader.class, DefaultArtifactDescriptorReader.class);
    locator.addService(VersionResolver.class, DefaultVersionResolver.class);
    locator.addService(VersionRangeResolver.class, DefaultVersionRangeResolver.class);
    locator.addService(MetadataGeneratorFactory.class, SnapshotMetadataGeneratorFactory.class);
    locator.addService(MetadataGeneratorFactory.class, VersionsMetadataGeneratorFactory.class);
    return locator;
  }

  /**
   * Creates a new Maven-like repository system session by initializing the session with values
   * typical for Maven-based resolution. In more detail, this method configures settings relevant
   * for the processing of dependency graphs, most other settings remain at their generic default
   * value. Use the various setters to further configure the session with authentication, mirror,
   * proxy and other information required for your environment.
   * 
   * @return The new repository system session, never {@code null}.
   */
  public static DefaultRepositorySystemSession newSession() {
    DefaultRepositorySystemSession session = new DefaultRepositorySystemSession();

    DependencyTraverser depTraverser = new FatArtifactTraverser();
    session.setDependencyTraverser(depTraverser);

    DependencyManager depManager = new ClassicDependencyManager();
    session.setDependencyManager(depManager);

    DependencySelector depFilter = new AndDependencySelector(new ScopeDependencySelector("test", "provided"),
        new OptionalDependencySelector(), new ExclusionDependencySelector());
    session.setDependencySelector(depFilter);

    DependencyGraphTransformer transformer = new ConflictResolver(new NearestVersionSelector(), new JavaScopeSelector(),
        new SimpleOptionalitySelector(), new JavaScopeDeriver());
    new ChainedDependencyGraphTransformer(transformer, new JavaDependencyContextRefiner());
    session.setDependencyGraphTransformer(transformer);

    DefaultArtifactTypeRegistry stereotypes = new DefaultArtifactTypeRegistry();
    stereotypes.add(new DefaultArtifactType("pom"));
    stereotypes.add(new DefaultArtifactType("maven-plugin", "jar", "", "java"));
    stereotypes.add(new DefaultArtifactType("jar", "jar", "", "java"));
    stereotypes.add(new DefaultArtifactType("ejb", "jar", "", "java"));
    stereotypes.add(new DefaultArtifactType("ejb-client", "jar", "client", "java"));
    stereotypes.add(new DefaultArtifactType("test-jar", "jar", "tests", "java"));
    stereotypes.add(new DefaultArtifactType("javadoc", "jar", "javadoc", "java"));
    stereotypes.add(new DefaultArtifactType("java-source", "jar", "sources", "java", false, false));
    stereotypes.add(new DefaultArtifactType("war", "war", "", "java", false, true));
    stereotypes.add(new DefaultArtifactType("ear", "ear", "", "java", false, true));
    stereotypes.add(new DefaultArtifactType("rar", "rar", "", "java", false, true));
    stereotypes.add(new DefaultArtifactType("par", "par", "", "java", false, true));
    session.setArtifactTypeRegistry(stereotypes);

    session.setArtifactDescriptorPolicy(new SimpleArtifactDescriptorPolicy(true, true));

    Properties sysProps = System.getProperties();
    session.setSystemProperties(sysProps);
    session.setConfigProperties(sysProps);

    return session;
  }

}
